When switched on, the grinding machine accelerates from rest to its operating speed of 2940 rev/min in 5 seconds. When switched off, it coasts to rest in 36 seconds. Determine the number of revolutions turned during both the startup and shutdown periods. Also determine the number of revolutions turned during the first half of each period. Assume uniform angular acceleration in both cases.

Elements Of Electromagnetics
7th Edition
ISBN:9780190698614
Author:Sadiku, Matthew N. O.
Publisher:Sadiku, Matthew N. O.
ChapterMA: Math Assessment
Section: Chapter Questions
Problem 1.1MA
icon
Related questions
Question
### Problem Statement

When switched on, the grinding machine accelerates from rest to its operating speed of 2940 revolutions per minute (rev/min) in 5 seconds. When switched off, it coasts to rest in 36 seconds. Determine the number of revolutions turned during both the startup and shutdown periods. Also, determine the number of revolutions turned during the first half of each period. Assume uniform angular acceleration in both cases.

### Diagram

The diagram illustrates a grinding machine with a rotating wheel. There is a notation indicating the angular velocity (ω) of the grinding wheel, suggesting the machine's rotational motion.

### Answers:

Number of revolutions during each period.
- **Startup:** Δθ = [Text Box] rev
- **Shutdown:** Δθ = [Text Box] rev

Modify the above text boxes with appropriate values as calculated or enter the corresponding input in the provided fields.

**Note:** To solve the problem, apply the kinematic equations for rotational motion with uniform angular acceleration. Use the following steps to derive the required values:

1. **Determine angular acceleration:** 
   - For startup: \(\alpha_{\text{startup}} = \frac{\omega_{\text{final}}}{t_{\text{startup}}}\)
   - For shutdown: \(\alpha_{\text{shutdown}} = \frac{-\omega_{\text{initial}}}{t_{\text{shutdown}}}\)

2. **Calculate the total number of revolutions (Δθ):**
   - Use the equation: \(\Delta\theta = \frac{1}{2} \alpha t^2\)
   - For startup and shutdown, respectively.

3. **Determine the number of revolutions in the first half of each period:**
   - Split the total angular displacement accordingly.

Assumptions and angular acceleration values will be applied to determine the required revolution numbers during startup and shutdown.
Transcribed Image Text:### Problem Statement When switched on, the grinding machine accelerates from rest to its operating speed of 2940 revolutions per minute (rev/min) in 5 seconds. When switched off, it coasts to rest in 36 seconds. Determine the number of revolutions turned during both the startup and shutdown periods. Also, determine the number of revolutions turned during the first half of each period. Assume uniform angular acceleration in both cases. ### Diagram The diagram illustrates a grinding machine with a rotating wheel. There is a notation indicating the angular velocity (ω) of the grinding wheel, suggesting the machine's rotational motion. ### Answers: Number of revolutions during each period. - **Startup:** Δθ = [Text Box] rev - **Shutdown:** Δθ = [Text Box] rev Modify the above text boxes with appropriate values as calculated or enter the corresponding input in the provided fields. **Note:** To solve the problem, apply the kinematic equations for rotational motion with uniform angular acceleration. Use the following steps to derive the required values: 1. **Determine angular acceleration:** - For startup: \(\alpha_{\text{startup}} = \frac{\omega_{\text{final}}}{t_{\text{startup}}}\) - For shutdown: \(\alpha_{\text{shutdown}} = \frac{-\omega_{\text{initial}}}{t_{\text{shutdown}}}\) 2. **Calculate the total number of revolutions (Δθ):** - Use the equation: \(\Delta\theta = \frac{1}{2} \alpha t^2\) - For startup and shutdown, respectively. 3. **Determine the number of revolutions in the first half of each period:** - Split the total angular displacement accordingly. Assumptions and angular acceleration values will be applied to determine the required revolution numbers during startup and shutdown.
Expert Solution
trending now

Trending now

This is a popular solution!

steps

Step by step

Solved in 2 steps

Blurred answer
Knowledge Booster
Dynamics
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, mechanical-engineering and related others by exploring similar questions and additional content below.
Recommended textbooks for you
Elements Of Electromagnetics
Elements Of Electromagnetics
Mechanical Engineering
ISBN:
9780190698614
Author:
Sadiku, Matthew N. O.
Publisher:
Oxford University Press
Mechanics of Materials (10th Edition)
Mechanics of Materials (10th Edition)
Mechanical Engineering
ISBN:
9780134319650
Author:
Russell C. Hibbeler
Publisher:
PEARSON
Thermodynamics: An Engineering Approach
Thermodynamics: An Engineering Approach
Mechanical Engineering
ISBN:
9781259822674
Author:
Yunus A. Cengel Dr., Michael A. Boles
Publisher:
McGraw-Hill Education
Control Systems Engineering
Control Systems Engineering
Mechanical Engineering
ISBN:
9781118170519
Author:
Norman S. Nise
Publisher:
WILEY
Mechanics of Materials (MindTap Course List)
Mechanics of Materials (MindTap Course List)
Mechanical Engineering
ISBN:
9781337093347
Author:
Barry J. Goodno, James M. Gere
Publisher:
Cengage Learning
Engineering Mechanics: Statics
Engineering Mechanics: Statics
Mechanical Engineering
ISBN:
9781118807330
Author:
James L. Meriam, L. G. Kraige, J. N. Bolton
Publisher:
WILEY